Add base:: to string16s in win8/.

win8/metro_driver/chrome_url_launch_handler.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_UI_METRO_DRIVER_CHROME_URL_LAUNCH_HANDLER_H_
 #define CHROME_BROWSER_UI_METRO_DRIVER_CHROME_URL_LAUNCH_HANDLER_H_
 
 #include <string>
 #include <windows.applicationmodel.core.h>
 #include <Windows.applicationModel.search.h>
@@ skipping 19 matching lines @@
   void Activate(winapp::Activation::IActivatedEventArgs* args);
 
  private:
   // Invoked when we receive search notifications in metro chrome.
   template<class T> void HandleSearchRequest(T* args);
 
   HRESULT OnQuerySubmitted(
       winapp::Search::ISearchPane* search_pane,
       winapp::Search::ISearchPaneQuerySubmittedEventArgs* args);
 
-  string16 GetUrlFromLaunchArgs(const string16& launch_args);
+  base::string16 GetUrlFromLaunchArgs(const base::string16& launch_args);
 
   // Invoked when a url is navigated from a metro app or in the metro
   // shelf.
   void HandleProtocolLaunch(
       winapp::Activation::IProtocolActivatedEventArgs* args);
 
   // Invoked when the app is launched normally
   void HandleLaunch(winapp::Activation::ILaunchActivatedEventArgs* args);
 
   // Helper function to initiate a navigation or search request in chrome.
   void InitiateNavigationOrSearchRequest(const wchar_t* url,
                                          const wchar_t* search_string);
 
   Microsoft::WRL::ComPtr<winapp::Search::ISearchPane> search_pane_;
   EventRegistrationToken query_submitted_token_;
 };
 
 #endif  // CHROME_BROWSER_UI_METRO_DRIVER_CHROME_URL_LAUNCH_HANDLER_H_